AMAZIN' MISTAKES: If the Mets deal the dynamic Jose Reyes (above, after being picked off first base last night), The Post's Mike Vaccaro says, they'll be repeating the mistakes the team made in 1977, when they dumped Tom Seaver, inspiring a memorable Post back page (inset) and sparking nearly a decade of mediocrity. Photo: UPI

If you are old enough to re member the spring of 1977, your memory will not allow you to ignore the troubling parallels of what awaits the Mets across the next few months. If you are old enough to remember the last time the Mets permitted a franchise player in his prime — Tom Seaver — to simply walk away for 30 pieces of silver, if you remember the pall that descended upon the franchise then and didn’t clear for years . . .

Well, that is why you try to ignore it.

And that is why you can’t.

That is why the louder the drumbeat becomes for the exile of Jose Reyes, the more you want to stand up and declare that the whole world has gone crazy. Because Reyes isn’t the kind of player you ship out in exchange for parts and pieces that may or may not build the foundation for the future.

Reyes is a foundation for the future. If not for the Mets, then for someone else. And if it isn’t for the Mets, then that might be the kind of hint — the same way Seaver was, once upon a time — that the people in charge of the baseball team simply don’t have the stomach (or the savings) for the fight that is achieving and maintaining relevance in baseball New York.

“I knew Jose was good,” manager Terry Collins said yesterday, before the Mets clipped the Dodgers, 4-2, at Citi Field thanks, in part, to two hits and an RBI from his shortstop. “But until you see him every day you can’t appreciate that he’s this good.”

Collins was speaking at the end of a week in which Reyes had been especially electric. Tuesday he reached base in all six of his plate appearances (including three walks, which had to catch the eye of the Mets’ “Moneyball” set). Friday, he hit two triples and added a double.

Is he perfect? He is not. There are still times when he does the inexplicable on the basepaths, and last night he did it twice: picked off at first by the catcher while daydreaming, then thrown out in a rundown between second and third on a grounder hit in front of him. Do you live with that? If you’re smart, you do.

Now, you can offer a lot of reasonable suggestions for why the Mets ought to be willing to part with Reyes before July 31, or why it makes fiscal sense for them to avoid handing out a Carl Crawford-like deal during the exclusive window they’d have to negotiate with him if he stays through October. And all of those reasons would make sense if Reyes were even 30 years old, which happens to be what Crawford will turn in August, or 32 years old, which is what Jayson Werth will turn in 12 days.

But Reyes won’t be 28 until next month. If his past injuries inspire caution, his present performance should inspire something else. Nobody is suggesting that the Mets have to go on a silly offseason spending spree to prove they remain viable, or should pledge to spend some of their new capital on marginal help. Nevertheless, it should be a referendum on how seriously they expect to be taken as league players if they simply allow a player like this to leave.

Thirty-four years ago next month, they allowed Seaver to leave. The circumstances aren’t identical: Seaver had soured on the Mets and on his out-of-date contract, and he wasn’t bashful about airing his discontent. But the truth is this: The man who ran the Mets, M. Donald Grant, made the business decision that Seaver’s quirks and foibles were no longer worth having him pitch every fifth day. That explains why Seaver was gone by June 15, 1977, and also explains why Grant was gone not long after.

Reyes’ injuries have made it easy the past few years to forget just how dynamic he is, and also just how young he still is. His season to date — .326 average, .377 OBP, 12 steals, five triples, virtually flawless defense — ought to serve as a reminder.

You cut ties with such a player at our own risk. The Mets, more than any team in baseball, ought to already know that.